1. Field of the Invention
This invention relates to low cost sensors and sensing systems and methods for sensing physical phenomena such as electric current and voltage values, magnetic fields and the like.
More particularly, the invention relates to low cost sensors and sensing systems of the abovenoted type which employ ferrite sensors that exhibit anistropic magneto-resistive effects.
2. Background Problem
There is a large demand for low cost systems and devices for measuring physical phenomena such as electric current and voltage values, magnetic field strengths and the like. For example, considering the number of residential dwellings in the mainland U.S.A. it will be appreciated that in order to monitor electric power consumption reliably and accurately in each of the residences, requires a substantial investment in measuring instruments known as watthour meters. Each of these instruments requires a sensor device for sensing the value of electric current supplied to the residence as well as a sensor for sensing the voltage at which such electric current is supplied. It will be appreciated therefore that in the case of electric utilities which normally provide such measuring instruments, the capital investment involved in installing and maintaining the instruments is substantial. If new sensing techniques, systems and devices can be devised which will reduce the cost of the measuring instruments even slightly, a substantial savings can be effected.